It looks like leafminer damage, from fly larvae. They tunnel between the upper/lower epidermis, so fresh damage will look translucent, before drying up. If you look at the undersides of leaves you may see little white eggs, which can be rubbed off.

_________________Formerly Kaleicious. I still love kale, but no more than lots of other garden greens too! Orach is currently my favorite.

Hi, I just looked it up in my gardening book and it says that it is downy mildew caused by wet and cold weather, so you are right in thinking that it could be the rain. It says to pick off the diseased leaves as no treatment is available. To prevent it from occurring (a bit late for you guys, I know), practise crop rotation and make sure that the soil is well drained.

crop rotation and soil drainage aren't an issue for me. we move stuff around every year and the beds are raised, so the soil drains well. it's just been raining so much that nothing can dry out before it gets drowned again. oh well. i'll pick off the crappy looking leaves and hope that the next few days of forecasted sunshine are enough to give the poor things a chance to breathe.thanks for looking it up!

_________________I'm one of those vegans that cuts corners when it comes to things like breastfeeding and stabbing you in the face~PranjalThat story would be adorable if it didn't end with herpes. ~Mo